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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Gaspar Santiago
Gaspar Santiago
3,377 Points

Ok so I created the new method to add a single item to the shopping cart and I'm still getting a compiling error

I keep getting asked if I un-commented the single item add method, which I did and still no go.

Example.java
public class Example {

  public static void main(String[] args) {
    ShoppingCart cart = new ShoppingCart();
    Product pez = new Product("Cherry PEZ refill (12 pieces)");
    cart.addItem(pez, 5);
    /* Since a quantity of 1 is such a common argument when adding a product to the cart,
     * your fellow developers have asked you to make the following code work, as well as keeping
     * the ability to add a product and a quantity.
     */
    Product dispenser = new Product("Yoda PEZ dispenser");
    cart.addItem(dispenser);
  }

}
ShoppingCart.java
public class ShoppingCart {

  public void addItem(Product item) {
    System.out.printf("Adding one of $s to the cart.%n", item.getName());
  }

  public void addItem(Product item, int quantity) {
    System.out.printf("Adding %d of %s to the cart.%n", quantity, item.getName());
    /* Other code omitted for clarity. Please imagine
       lots and lots of code here. Don't repeat it. 
    */
  }
}
Product.java
public class Product {
  /* Other code omitted for clarity, but you could imagine
     it would store price, options like size and color
  */
  private String mName;

  public Product(String name) {
      mName = name;
  }

  public String getName() {
      return mName;
  }
}

2 Answers

Simon Coates
Simon Coates
28,693 Points

shopping cart should be something like:

public class ShoppingCart {

  public void addItem(Product item, int quantity) {
    System.out.printf("Adding %d of %s to the cart.%n", quantity, item.getName());
    /* Other code omitted for clarity. Please imagine
       lots and lots of code here. Don't repeat it. 
    */
  }
    public void addItem(Product item) {
    addItem(item, 1);
  }
}

or

public class ShoppingCart {

  public void addItem(Product item, int quantity) {
    System.out.printf("Adding %d of %s to the cart.%n", quantity, item.getName());
    /* Other code omitted for clarity. Please imagine      lots and lots of code here. Don't repeat it.     */
  }

  public void addItem(Product item) {
    System.out.printf("Adding %d of %s to the cart.%n", 1, item.getName());
  }
}

You're almost there!

In your addItem(Product item) method, you need to specify the "quantity" of 1. While you don't pass that in as an argument, it still need to be placed in the output String.

  public void addItem(Product item) {
    System.out.printf("Adding one of %s to the cart. %n", 1, item.getName());
  }

It should work when you make that small change!